Before I start on the topic of how to requeen an aggressive colony I would just like to talk a little about what we term as Aggressive. I have been working with honeybees for over 12 years and in all of those years I have only ever encountered 2 colonies that were “Aggressive”. One of those was not a colony we owned but one we did end up with and it was troublesome to requeen. I have also experienced bees that “buzz” and “bounce” off you, and whilst this is perhaps not the most desirable trait it definitely does not fall under the description of “Aggression”. Often there is a reason for the colony behaviour. If, your normally nice bees suddenly turn nasty almost overnight then there is probably a very good reason.
The other experience I encountered with a colony that was extremely aggressive was with one of our own colonies; it was on a pollination contract at the time and it just went for me literally straight away. I can recall there being of lot of activity as I removed the roof and as soon as I lifted the crownboard that was it. I am pleased to say that I have never experienced that again, and I hope I never do! I did find out why the bees were so aggressive towards me and actually they had every right to be as they were defending themselves. They were pollinating raspberries and, rather sadly the grower did not have orders for the forthcoming fruit crop, so they turned the water supply off to the greenhouses as they could not afford to keep the plants alive. The nectar source had suddenly been turned off and therefore their food stores were now very precious to them as it was mid-season and the colony numbers were big and still growing.
Bad handling of your colony can upset them as well inappropriate use of smoke. Bees are still wild animals and they have a naturally evolved defence mechanism that is there to ward off predators. If you go in all guns blazing with lots of smoke and noise and rough handling, you should not be surprised if you bees are less than happy to see you!
If you do have an aggressive colony there is always something that can be done. I have heard beekeepers say they are so aggressive I have no option but to kill them. You do have options and whilst killing them may be one of them, it should always be as a last resort.
If you are feel you are able to inspect the colony to locate the queen then do so. You will probably need to use more smoke than usual, which could be counterproductive as it may make the queen run more and she may end up being somewhere you’d least expect her to be. You can try using sugar water in a spray instead off smoke, as this will also stop the bees flying and they will hopefully be side-tracked by the sugar water too. If you inspect at the height of the day on a nice warm sunny day then most of the flying bees should be out and therefore you will have less bees in the colony to deal with.
If however, the colony is so evil that it makes it impossible to inspect, then you can try doing something to reduce the volume of bees you are dealing with. Again you should make sure it is a nice warm sunny day as you need the flying bees to be out flying. The idea is that you move the hive several feet away from it’s existing location, place a queen-right nuc or small colony on the original location and you will find the flying bees, and these are more likely to be the ones that sting you, will return to original site and go into the new colony there. It would be a good idea to cage the queen in this new colony to protected her from the returning bees, unless of course this queen was one you were going to replace anyway and then it won’t matter if they do overwhelm her.
If you move the hive in the morning then by early to mid-afternoon, depending on what time of the year it is, the vast majority of flying bees will have gone out foraging and will return to new colony you located on te original site. The activity at the entrance will be much less and there should be mainly young bees left in the colony. These younger bees will be far less aggressive and therefore will make it easier to inspect. This will also mean there is a much better chance of them accepting the new queen too. Now go through the colony, find the queen and kill her. Do not under any circumstances be tempted to keep her!
Put your new queen, still in her introduction cage with the tab on so it is sealed, into the colony and reassemble your hive. Leave the colony for 48 hours then go in and do an inspection and either remove the tab from the queen cage to let the bees let her out, or you can carefully open the cage and release her yourself.
If however, the colony is still too difficult for you to go through and you can’t find the queen, then you could try splitting the colony down. Take out some of the frames and bees to make up 2 or 3 smaller nucs which you can leave for a few hours and then go back and inspect and see if you can find the queen. You may see from the behaviour of the bees which colony is likely to have the queen in. Once you have found the queen and killed her you can replace the combs back into one hive and add the new caged queen as described in the previous paragraphs.
If you did manage to find the old queen in the colony without splitting it down and reducing the bee numbers etc then do bear in mind that the bees may well overwhelm the new queen when you put her in. We have had a better acceptance rate by removing the old queen and leaving them for a few hours before putting the new queen cage in. I would suggest that at this stage you do spray the bees with sugar water before putting in the new queen and again leave the cage sealed for 48 hours so you can check she is still ok.
You may find the bees temperament improves just with the new queen heading the colony but in most cases you may need to wait until the new brood emerges that your new queen has laid to see a change in temperament.
If your bees do kill the queen and you try again only to find they kill her as well, the best thing would be to let them make a new queen using a frame of eggs from a colony that you do like the temperament from. Or you may have a queen cell that you can carefully take from another colony and see if they accept that.
Hopefully this will be of help to you, whatever your plan, remember to stay calm and focused, and do ask a friend to be there for reassurance and support if you can.